client.go

/*
OpenProject API V3 (Stable)

You're looking at the current **stable** documentation of the OpenProject APIv3. If you're interested in the current development version, please go to [github.com/opf](https://github.com/opf/openproject/tree/dev/docs/api/apiv3).  ## Introduction  The documentation for the APIv3 is written according to the [OpenAPI 3.0 Specification](https://swagger.io/specification/). You can either view the static version of this documentation on the [website](https://www.openproject.org/docs/api/introduction/) or the interactive version, rendered with [OpenAPI Explorer](https://github.com/Rhosys/openapi-explorer/blob/main/README.md), in your OpenProject installation under `/api/docs`. In the latter you can try out the various API endpoints directly interacting with our OpenProject data. Moreover you can access the specification source itself under `/api/v3/spec.json` and `/api/v3/spec.yml` (e.g. [here](https://community.openproject.org/api/v3/spec.yml)).  The APIv3 is a hypermedia REST API, a shorthand for \"Hypermedia As The Engine Of Application State\" (HATEOAS). This means that each endpoint of this API will have links to other resources or actions defined in the resulting body.  These related resources and actions for any given resource will be context sensitive. For example, only actions that the authenticated user can take are being rendered. This can be used to dynamically identify actions that the user might take for any given response.  As an example, if you fetch a work package through the [Work Package endpoint](https://www.openproject.org/docs/api/endpoints/work-packages/), the `update` link will only be present when the user you authenticated has been granted a permission to update the work package in the assigned project.  ## HAL+JSON  HAL is a simple format that gives a consistent and easy way to hyperlink between resources in your API. Read more in the following specification: [https://tools.ietf.org/html/draft-kelly-json-hal-08](https://tools.ietf.org/html/draft-kelly-json-hal-08)  **OpenProject API implementation of HAL+JSON format** enriches JSON and introduces a few meta properties:  - `_type` - specifies the type of the resource (e.g.: WorkPackage, Project) - `_links` - contains all related resource and action links available for the resource - `_embedded` - contains all embedded objects  HAL does not guarantee that embedded resources are embedded in their full representation, they might as well be partially represented (e.g. some properties can be left out). However in this API you have the guarantee that whenever a resource is **embedded**, it is embedded in its **full representation**.  ## API response structure  All API responses contain a single HAL+JSON object, even collections of objects are technically represented by a single HAL+JSON object that itself contains its members. More details on collections can be found in the [Collections Section](https://www.openproject.org/docs/api/collections/).  ## Authentication  The API supports the following authentication schemes: OAuth2, session based authentication, and basic auth.  Depending on the settings of the OpenProject instance many resources can be accessed without being authenticated. In case the instance requires authentication on all requests the client will receive an **HTTP 401** status code in response to any request.  Otherwise unauthenticated clients have all the permissions of the anonymous user.  ### Session-based Authentication  This means you have to login to OpenProject via the Web-Interface to be authenticated in the API. This method is well-suited for clients acting within the browser, like the Angular-Client built into OpenProject.  In this case, you always need to pass the HTTP header `X-Requested-With \"XMLHttpRequest\"` for authentication.  ### API Key through Basic Auth  Users can authenticate towards the API v3 using basic auth with the user name `apikey` (NOT your login) and the API key as the password. Users can find their API key on their account page.  Example:  ```shell API_KEY=2519132cdf62dcf5a66fd96394672079f9e9cad1 curl -u apikey:$API_KEY https://community.openproject.org/api/v3/users/42 ```  ### OAuth2.0 authentication  OpenProject allows authentication and authorization with OAuth2 with *Authorization code flow*, as well as *Client credentials* operation modes.  To get started, you first need to register an application in the OpenProject OAuth administration section of your installation. This will save an entry for your application with a client unique identifier (`client_id`) and an accompanying secret key (`client_secret`).  You can then use one the following guides to perform the supported OAuth 2.0 flows:  - [Authorization code flow](https://oauth.net/2/grant-types/authorization-code)  - [Authorization code flow with PKCE](https://doorkeeper.gitbook.io/guides/ruby-on-rails/pkce-flow), recommended for clients unable to keep the client_secret confidential.  - [Client credentials](https://oauth.net/2/grant-types/client-credentials/) - Requires an application to be bound to an impersonating user for non-public access  ### Why not username and password?  The simplest way to do basic auth would be to use a user's username and password naturally. However, OpenProject already has supported API keys in the past for the API v2, though not through basic auth.  Using **username and password** directly would have some advantages:  * It is intuitive for the user who then just has to provide those just as they would when logging into OpenProject.  * No extra logic for token management necessary.  On the other hand using **API keys** has some advantages too, which is why we went for that:  * If compromised while saved on an insecure client the user only has to regenerate the API key instead of changing their password, too.  * They are naturally long and random which makes them invulnerable to dictionary attacks and harder to crack in general.  Most importantly users may not actually have a password to begin with. Specifically when they have registered through an OpenID Connect provider.  ## Cross-Origin Resource Sharing (CORS)  By default, the OpenProject API is _not_ responding with any CORS headers. If you want to allow cross-domain AJAX calls against your OpenProject instance, you need to enable CORS headers being returned.  Please see [our API settings documentation](https://www.openproject.org/docs/system-admin-guide/api-and-webhooks/) on how to selectively enable CORS.  ## Allowed HTTP methods  - `GET` - Get a single resource or collection of resources  - `POST` - Create a new resource or perform  - `PATCH` - Update a resource  - `DELETE` - Delete a resource  ## Compression  Responses are compressed if requested by the client. Currently [gzip](https://www.gzip.org/) and [deflate](https://tools.ietf.org/html/rfc1951) are supported. The client signals the desired compression by setting the [`Accept-Encoding` header](https://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.3). If no `Accept-Encoding` header is send, `Accept-Encoding: identity` is assumed which will result in the API responding uncompressed.

API version: 3
*/

// Code generated by OpenAPI Generator (https://openapi-generator.tech); DO NOT EDIT.

package openproject

import (
	"bytes"
	"context"
	"encoding/json"
	"encoding/xml"
	"errors"
	"fmt"
	"io"
	"log"
	"mime/multipart"
	"net/http"
	"net/http/httputil"
	"net/url"
	"os"
	"path/filepath"
	"reflect"
	"regexp"
	"strconv"
	"strings"
	"time"
	"unicode/utf8"

)

var (
	JsonCheck       = regexp.MustCompile(`(?i:(?:application|text)/(?:[^;]+\+)?json)`)
	XmlCheck        = regexp.MustCompile(`(?i:(?:application|text)/(?:[^;]+\+)?xml)`)
	queryParamSplit = regexp.MustCompile(`(^|&)([^&]+)`)
	queryDescape    = strings.NewReplacer( "%5B", "[", "%5D", "]" )
)

// APIClient manages communication with the OpenProject API V3 (Stable) API v3
// In most cases there should be only one, shared, APIClient.
type APIClient struct {
	cfg    *Configuration
	common service // Reuse a single struct instead of allocating one for each service on the heap.

	// API Services

	ActionsCapabilitiesAPI *ActionsCapabilitiesAPIService

	ActivitiesAPI *ActivitiesAPIService

	AttachmentsAPI *AttachmentsAPIService

	BudgetsAPI *BudgetsAPIService

	CategoriesAPI *CategoriesAPIService

	CollectionsAPI *CollectionsAPIService

	ConfigurationAPI *ConfigurationAPIService

	CustomActionsAPI *CustomActionsAPIService

	CustomOptionsAPI *CustomOptionsAPIService

	DocumentsAPI *DocumentsAPIService

	FileLinksAPI *FileLinksAPIService

	FormsAPI *FormsAPIService

	GridsAPI *GridsAPIService

	GroupsAPI *GroupsAPIService

	HelpTextsAPI *HelpTextsAPIService

	MeetingsAPI *MeetingsAPIService

	MembershipsAPI *MembershipsAPIService

	NewsAPI *NewsAPIService

	NotificationsAPI *NotificationsAPIService

	OAuth2API *OAuth2APIService

	PostsAPI *PostsAPIService

	PreviewingAPI *PreviewingAPIService

	PrincipalsAPI *PrincipalsAPIService

	PrioritiesAPI *PrioritiesAPIService

	ProjectsAPI *ProjectsAPIService

	QueriesAPI *QueriesAPIService

	QueryColumnsAPI *QueryColumnsAPIService

	QueryFilterInstanceSchemaAPI *QueryFilterInstanceSchemaAPIService

	QueryFiltersAPI *QueryFiltersAPIService

	QueryOperatorsAPI *QueryOperatorsAPIService

	QuerySortBysAPI *QuerySortBysAPIService

	RelationsAPI *RelationsAPIService

	RevisionsAPI *RevisionsAPIService

	RolesAPI *RolesAPIService

	RootAPI *RootAPIService

	SchemasAPI *SchemasAPIService

	StatusesAPI *StatusesAPIService

	TimeEntriesAPI *TimeEntriesAPIService

	TimeEntryActivitiesAPI *TimeEntryActivitiesAPIService

	TypesAPI *TypesAPIService

	UserPreferencesAPI *UserPreferencesAPIService

	UsersAPI *UsersAPIService

	ValuesPropertyAPI *ValuesPropertyAPIService

	VersionsAPI *VersionsAPIService

	ViewsAPI *ViewsAPIService

	WikiPagesAPI *WikiPagesAPIService

	WorkPackagesAPI *WorkPackagesAPIService

	WorkScheduleAPI *WorkScheduleAPIService
}

type service struct {
	client *APIClient
}

// NewAPIClient creates a new API client. Requires a userAgent string describing your application.
// optionally a custom http.Client to allow for advanced features such as caching.
func NewAPIClient(cfg *Configuration) *APIClient {
	if cfg.HTTPClient == nil {
		cfg.HTTPClient = http.DefaultClient
	}

	c := &APIClient{}
	c.cfg = cfg
	c.common.client = c

	// API Services
	c.ActionsCapabilitiesAPI = (*ActionsCapabilitiesAPIService)(&c.common)
	c.ActivitiesAPI = (*ActivitiesAPIService)(&c.common)
	c.AttachmentsAPI = (*AttachmentsAPIService)(&c.common)
	c.BudgetsAPI = (*BudgetsAPIService)(&c.common)
	c.CategoriesAPI = (*CategoriesAPIService)(&c.common)
	c.CollectionsAPI = (*CollectionsAPIService)(&c.common)
	c.ConfigurationAPI = (*ConfigurationAPIService)(&c.common)
	c.CustomActionsAPI = (*CustomActionsAPIService)(&c.common)
	c.CustomOptionsAPI = (*CustomOptionsAPIService)(&c.common)
	c.DocumentsAPI = (*DocumentsAPIService)(&c.common)
	c.FileLinksAPI = (*FileLinksAPIService)(&c.common)
	c.FormsAPI = (*FormsAPIService)(&c.common)
	c.GridsAPI = (*GridsAPIService)(&c.common)
	c.GroupsAPI = (*GroupsAPIService)(&c.common)
	c.HelpTextsAPI = (*HelpTextsAPIService)(&c.common)
	c.MeetingsAPI = (*MeetingsAPIService)(&c.common)
	c.MembershipsAPI = (*MembershipsAPIService)(&c.common)
	c.NewsAPI = (*NewsAPIService)(&c.common)
	c.NotificationsAPI = (*NotificationsAPIService)(&c.common)
	c.OAuth2API = (*OAuth2APIService)(&c.common)
	c.PostsAPI = (*PostsAPIService)(&c.common)
	c.PreviewingAPI = (*PreviewingAPIService)(&c.common)
	c.PrincipalsAPI = (*PrincipalsAPIService)(&c.common)
	c.PrioritiesAPI = (*PrioritiesAPIService)(&c.common)
	c.ProjectsAPI = (*ProjectsAPIService)(&c.common)
	c.QueriesAPI = (*QueriesAPIService)(&c.common)
	c.QueryColumnsAPI = (*QueryColumnsAPIService)(&c.common)
	c.QueryFilterInstanceSchemaAPI = (*QueryFilterInstanceSchemaAPIService)(&c.common)
	c.QueryFiltersAPI = (*QueryFiltersAPIService)(&c.common)
	c.QueryOperatorsAPI = (*QueryOperatorsAPIService)(&c.common)
	c.QuerySortBysAPI = (*QuerySortBysAPIService)(&c.common)
	c.RelationsAPI = (*RelationsAPIService)(&c.common)
	c.RevisionsAPI = (*RevisionsAPIService)(&c.common)
	c.RolesAPI = (*RolesAPIService)(&c.common)
	c.RootAPI = (*RootAPIService)(&c.common)
	c.SchemasAPI = (*SchemasAPIService)(&c.common)
	c.StatusesAPI = (*StatusesAPIService)(&c.common)
	c.TimeEntriesAPI = (*TimeEntriesAPIService)(&c.common)
	c.TimeEntryActivitiesAPI = (*TimeEntryActivitiesAPIService)(&c.common)
	c.TypesAPI = (*TypesAPIService)(&c.common)
	c.UserPreferencesAPI = (*UserPreferencesAPIService)(&c.common)
	c.UsersAPI = (*UsersAPIService)(&c.common)
	c.ValuesPropertyAPI = (*ValuesPropertyAPIService)(&c.common)
	c.VersionsAPI = (*VersionsAPIService)(&c.common)
	c.ViewsAPI = (*ViewsAPIService)(&c.common)
	c.WikiPagesAPI = (*WikiPagesAPIService)(&c.common)
	c.WorkPackagesAPI = (*WorkPackagesAPIService)(&c.common)
	c.WorkScheduleAPI = (*WorkScheduleAPIService)(&c.common)

	return c
}

func atoi(in string) (int, error) {
	return strconv.Atoi(in)
}

// selectHeaderContentType select a content type from the available list.
func selectHeaderContentType(contentTypes []string) string {
	if len(contentTypes) == 0 {
		return ""
	}
	if contains(contentTypes, "application/json") {
		return "application/json"
	}
	return contentTypes[0] // use the first content type specified in 'consumes'
}

// selectHeaderAccept join all accept types and return
func selectHeaderAccept(accepts []string) string {
	if len(accepts) == 0 {
		return ""
	}

	if contains(accepts, "application/json") {
		return "application/json"
	}

	return strings.Join(accepts, ",")
}

// contains is a case insensitive match, finding needle in a haystack
func contains(haystack []string, needle string) bool {
	for _, a := range haystack {
		if strings.EqualFold(a, needle) {
			return true
		}
	}
	return false
}

// Verify optional parameters are of the correct type.
func typeCheckParameter(obj interface{}, expected string, name string) error {
	// Make sure there is an object.
	if obj == nil {
		return nil
	}

	// Check the type is as expected.
	if reflect.TypeOf(obj).String() != expected {
		return fmt.Errorf("expected %s to be of type %s but received %s", name, expected, reflect.TypeOf(obj).String())
	}
	return nil
}

func parameterValueToString( obj interface{}, key string ) string {
	if reflect.TypeOf(obj).Kind() != reflect.Ptr {
		return fmt.Sprintf("%v", obj)
	}
	var param,ok = obj.(MappedNullable)
	if !ok {
		return ""
	}
	dataMap,err := param.ToMap()
	if err != nil {
		return ""
	}
	return fmt.Sprintf("%v", dataMap[key])
}

// parameterAddToHeaderOrQuery adds the provided object to the request header or url query
// supporting deep object syntax
func parameterAddToHeaderOrQuery(headerOrQueryParams interface{}, keyPrefix string, obj interface{}, collectionType string) {
	var v = reflect.ValueOf(obj)
	var value = ""
	if v == reflect.ValueOf(nil) {
		value = "null"
	} else {
		switch v.Kind() {
			case reflect.Invalid:
				value = "invalid"

			case reflect.Struct:
				if t,ok := obj.(MappedNullable); ok {
					dataMap,err := t.ToMap()
					if err != nil {
						return
					}
					parameterAddToHeaderOrQuery(headerOrQueryParams, keyPrefix, dataMap, collectionType)
					return
				}
				if t, ok := obj.(time.Time); ok {
					parameterAddToHeaderOrQuery(headerOrQueryParams, keyPrefix, t.Format(time.RFC3339Nano), collectionType)
					return
				}
				value = v.Type().String() + " value"
			case reflect.Slice:
				var indValue = reflect.ValueOf(obj)
				if indValue == reflect.ValueOf(nil) {
					return
				}
				var lenIndValue = indValue.Len()
				for i:=0;i<lenIndValue;i++ {
					var arrayValue = indValue.Index(i)
					parameterAddToHeaderOrQuery(headerOrQueryParams, keyPrefix, arrayValue.Interface(), collectionType)
				}
				return

			case reflect.Map:
				var indValue = reflect.ValueOf(obj)
				if indValue == reflect.ValueOf(nil) {
					return
				}
				iter := indValue.MapRange()
				for iter.Next() {
					k,v := iter.Key(), iter.Value()
					parameterAddToHeaderOrQuery(headerOrQueryParams, fmt.Sprintf("%s[%s]", keyPrefix, k.String()), v.Interface(), collectionType)
				}
				return

			case reflect.Interface:
				fallthrough
			case reflect.Ptr:
				parameterAddToHeaderOrQuery(headerOrQueryParams, keyPrefix, v.Elem().Interface(), collectionType)
				return

			case reflect.Int, reflect.Int8, reflect.Int16,
				reflect.Int32, reflect.Int64:
				value = strconv.FormatInt(v.Int(), 10)
			case reflect.Uint, reflect.Uint8, reflect.Uint16,
				reflect.Uint32, reflect.Uint64, reflect.Uintptr:
				value = strconv.FormatUint(v.Uint(), 10)
			case reflect.Float32, reflect.Float64:
				value = strconv.FormatFloat(v.Float(), 'g', -1, 32)
			case reflect.Bool:
				value = strconv.FormatBool(v.Bool())
			case reflect.String:
				value = v.String()
			default:
				value = v.Type().String() + " value"
		}
	}

	switch valuesMap := headerOrQueryParams.(type) {
		case url.Values:
			if collectionType == "csv" && valuesMap.Get(keyPrefix) != "" {
				valuesMap.Set(keyPrefix, valuesMap.Get(keyPrefix) + "," + value)
			} else {
				valuesMap.Add(keyPrefix, value)
			}
			break
		case map[string]string:
			valuesMap[keyPrefix] = value
			break
	}
}

// helper for converting interface{} parameters to json strings
func parameterToJson(obj interface{}) (string, error) {
	jsonBuf, err := json.Marshal(obj)
	if err != nil {
		return "", err
	}
	return string(jsonBuf), err
}

// callAPI do the request.
func (c *APIClient) callAPI(request *http.Request) (*http.Response, error) {
	if c.cfg.Debug {
		dump, err := httputil.DumpRequestOut(request, true)
		if err != nil {
			return nil, err
		}
		log.Printf("\n%s\n", string(dump))
	}

	resp, err := c.cfg.HTTPClient.Do(request)
	if err != nil {
		return resp, err
	}

	if c.cfg.Debug {
		dump, err := httputil.DumpResponse(resp, true)
		if err != nil {
			return resp, err
		}
		log.Printf("\n%s\n", string(dump))
	}
	return resp, err
}

// Allow modification of underlying config for alternate implementations and testing
// Caution: modifying the configuration while live can cause data races and potentially unwanted behavior
func (c *APIClient) GetConfig() *Configuration {
	return c.cfg
}

type formFile struct {
		fileBytes []byte
		fileName string
		formFileName string
}

// prepareRequest build the request
func (c *APIClient) prepareRequest(
	ctx context.Context,
	path string, method string,
	postBody interface{},
	headerParams map[string]string,
	queryParams url.Values,
	formParams url.Values,
	formFiles []formFile) (localVarRequest *http.Request, err error) {

	var body *bytes.Buffer

	// Detect postBody type and post.
	if postBody != nil {
		contentType := headerParams["Content-Type"]
		if contentType == "" {
			contentType = detectContentType(postBody)
			headerParams["Content-Type"] = contentType
		}

		body, err = setBody(postBody, contentType)
		if err != nil {
			return nil, err
		}
	}

	// add form parameters and file if available.
	if strings.HasPrefix(headerParams["Content-Type"], "multipart/form-data") && len(formParams) > 0 || (len(formFiles) > 0) {
		if body != nil {
			return nil, errors.New("Cannot specify postBody and multipart form at the same time.")
		}
		body = &bytes.Buffer{}
		w := multipart.NewWriter(body)

		for k, v := range formParams {
			for _, iv := range v {
				if strings.HasPrefix(k, "@") { // file
					err = addFile(w, k[1:], iv)
					if err != nil {
						return nil, err
					}
				} else { // form value
					w.WriteField(k, iv)
				}
			}
		}
		for _, formFile := range formFiles {
			if len(formFile.fileBytes) > 0 && formFile.fileName != "" {
				w.Boundary()
				part, err := w.CreateFormFile(formFile.formFileName, filepath.Base(formFile.fileName))
				if err != nil {
						return nil, err
				}
				_, err = part.Write(formFile.fileBytes)
				if err != nil {
						return nil, err
				}
			}
		}

		// Set the Boundary in the Content-Type
		headerParams["Content-Type"] = w.FormDataContentType()

		// Set Content-Length
		headerParams["Content-Length"] = fmt.Sprintf("%d", body.Len())
		w.Close()
	}

	if strings.HasPrefix(headerParams["Content-Type"], "application/x-www-form-urlencoded") && len(formParams) > 0 {
		if body != nil {
			return nil, errors.New("Cannot specify postBody and x-www-form-urlencoded form at the same time.")
		}
		body = &bytes.Buffer{}
		body.WriteString(formParams.Encode())
		// Set Content-Length
		headerParams["Content-Length"] = fmt.Sprintf("%d", body.Len())
	}

	// Setup path and query parameters
	url, err := url.Parse(path)
	if err != nil {
		return nil, err
	}

	// Override request host, if applicable
	if c.cfg.Host != "" {
		url.Host = c.cfg.Host
	}

	// Override request scheme, if applicable
	if c.cfg.Scheme != "" {
		url.Scheme = c.cfg.Scheme
	}

	// Adding Query Param
	query := url.Query()
	for k, v := range queryParams {
		for _, iv := range v {
			query.Add(k, iv)
		}
	}

	// Encode the parameters.
	url.RawQuery = queryParamSplit.ReplaceAllStringFunc(query.Encode(), func(s string) string {
		pieces := strings.Split(s, "=")
		pieces[0] = queryDescape.Replace(pieces[0])
		return strings.Join(pieces, "=")
	})

	// Generate a new request
	if body != nil {
		localVarRequest, err = http.NewRequest(method, url.String(), body)
	} else {
		localVarRequest, err = http.NewRequest(method, url.String(), nil)
	}
	if err != nil {
		return nil, err
	}

	// add header parameters, if any
	if len(headerParams) > 0 {
		headers := http.Header{}
		for h, v := range headerParams {
			headers[h] = []string{v}
		}
		localVarRequest.Header = headers
	}

	// Add the user agent to the request.
	localVarRequest.Header.Add("User-Agent", c.cfg.UserAgent)

	if ctx != nil {
		// add context to the request
		localVarRequest = localVarRequest.WithContext(ctx)

		// Walk through any authentication.

		// Basic HTTP Authentication
		if auth, ok := ctx.Value(ContextBasicAuth).(BasicAuth); ok {
			localVarRequest.SetBasicAuth(auth.UserName, auth.Password)
		}

	}

	for header, value := range c.cfg.DefaultHeader {
		localVarRequest.Header.Add(header, value)
	}
	return localVarRequest, nil
}

func (c *APIClient) decode(v interface{}, b []byte, contentType string) (err error) {
	if len(b) == 0 {
		return nil
	}
	if s, ok := v.(*string); ok {
		*s = string(b)
		return nil
	}
	if f, ok := v.(*os.File); ok {
		f, err = os.CreateTemp("", "HttpClientFile")
		if err != nil {
			return
		}
		_, err = f.Write(b)
		if err != nil {
			return
		}
		_, err = f.Seek(0, io.SeekStart)
		return
	}
	if f, ok := v.(**os.File); ok {
		*f, err = os.CreateTemp("", "HttpClientFile")
		if err != nil {
			return
		}
		_, err = (*f).Write(b)
		if err != nil {
			return
		}
		_, err = (*f).Seek(0, io.SeekStart)
		return
	}
	if XmlCheck.MatchString(contentType) {
		if err = xml.Unmarshal(b, v); err != nil {
			return err
		}
		return nil
	}
	if JsonCheck.MatchString(contentType) {
		if actualObj, ok := v.(interface{ GetActualInstance() interface{} }); ok { // oneOf, anyOf schemas
			if unmarshalObj, ok := actualObj.(interface{ UnmarshalJSON([]byte) error }); ok { // make sure it has UnmarshalJSON defined
				if err = unmarshalObj.UnmarshalJSON(b); err != nil {
					return err
				}
			} else {
				return errors.New("Unknown type with GetActualInstance but no unmarshalObj.UnmarshalJSON defined")
			}
		} else if err = json.Unmarshal(b, v); err != nil { // simple model
			return err
		}
		return nil
	}
	return errors.New("undefined response type")
}

// Add a file to the multipart request
func addFile(w *multipart.Writer, fieldName, path string) error {
	file, err := os.Open(filepath.Clean(path))
	if err != nil {
		return err
	}
	err = file.Close()
	if err != nil {
		return err
	}

	part, err := w.CreateFormFile(fieldName, filepath.Base(path))
	if err != nil {
		return err
	}
	_, err = io.Copy(part, file)

	return err
}

// Prevent trying to import "fmt"
func reportError(format string, a ...interface{}) error {
	return fmt.Errorf(format, a...)
}

// A wrapper for strict JSON decoding
func newStrictDecoder(data []byte) *json.Decoder {
	dec := json.NewDecoder(bytes.NewBuffer(data))
	dec.DisallowUnknownFields()
	return dec
}

// Set request body from an interface{}
func setBody(body interface{}, contentType string) (bodyBuf *bytes.Buffer, err error) {
	if bodyBuf == nil {
		bodyBuf = &bytes.Buffer{}
	}

	if reader, ok := body.(io.Reader); ok {
		_, err = bodyBuf.ReadFrom(reader)
	} else if fp, ok := body.(*os.File); ok {
		_, err = bodyBuf.ReadFrom(fp)
	} else if b, ok := body.([]byte); ok {
		_, err = bodyBuf.Write(b)
	} else if s, ok := body.(string); ok {
		_, err = bodyBuf.WriteString(s)
	} else if s, ok := body.(*string); ok {
		_, err = bodyBuf.WriteString(*s)
	} else if JsonCheck.MatchString(contentType) {
		err = json.NewEncoder(bodyBuf).Encode(body)
	} else if XmlCheck.MatchString(contentType) {
		var bs []byte
		bs, err = xml.Marshal(body)
		if err == nil {
			bodyBuf.Write(bs)
		}
	}

	if err != nil {
		return nil, err
	}

	if bodyBuf.Len() == 0 {
		err = fmt.Errorf("invalid body type %s\n", contentType)
		return nil, err
	}
	return bodyBuf, nil
}

// detectContentType method is used to figure out `Request.Body` content type for request header
func detectContentType(body interface{}) string {
	contentType := "text/plain; charset=utf-8"
	kind := reflect.TypeOf(body).Kind()

	switch kind {
	case reflect.Struct, reflect.Map, reflect.Ptr:
		contentType = "application/json; charset=utf-8"
	case reflect.String:
		contentType = "text/plain; charset=utf-8"
	default:
		if b, ok := body.([]byte); ok {
			contentType = http.DetectContentType(b)
		} else if kind == reflect.Slice {
			contentType = "application/json; charset=utf-8"
		}
	}

	return contentType
}

// Ripped from https://github.com/gregjones/httpcache/blob/master/httpcache.go
type cacheControl map[string]string

func parseCacheControl(headers http.Header) cacheControl {
	cc := cacheControl{}
	ccHeader := headers.Get("Cache-Control")
	for _, part := range strings.Split(ccHeader, ",") {
		part = strings.Trim(part, " ")
		if part == "" {
			continue
		}
		if strings.ContainsRune(part, '=') {
			keyval := strings.Split(part, "=")
			cc[strings.Trim(keyval[0], " ")] = strings.Trim(keyval[1], ",")
		} else {
			cc[part] = ""
		}
	}
	return cc
}

// CacheExpires helper function to determine remaining time before repeating a request.
func CacheExpires(r *http.Response) time.Time {
	// Figure out when the cache expires.
	var expires time.Time
	now, err := time.Parse(time.RFC1123, r.Header.Get("date"))
	if err != nil {
		return time.Now()
	}
	respCacheControl := parseCacheControl(r.Header)

	if maxAge, ok := respCacheControl["max-age"]; ok {
		lifetime, err := time.ParseDuration(maxAge + "s")
		if err != nil {
			expires = now
		} else {
			expires = now.Add(lifetime)
		}
	} else {
		expiresHeader := r.Header.Get("Expires")
		if expiresHeader != "" {
			expires, err = time.Parse(time.RFC1123, expiresHeader)
			if err != nil {
				expires = now
			}
		}
	}
	return expires
}

func strlen(s string) int {
	return utf8.RuneCountInString(s)
}

// GenericOpenAPIError Provides access to the body, error and model on returned errors.
type GenericOpenAPIError struct {
	body  []byte
	error string
	model interface{}
}

// Error returns non-empty string if there was an error.
func (e GenericOpenAPIError) Error() string {
	return e.error
}

// Body returns the raw bytes of the response
func (e GenericOpenAPIError) Body() []byte {
	return e.body
}

// Model returns the unpacked model of the error
func (e GenericOpenAPIError) Model() interface{} {
	return e.model
}

// format error message using title and detail when model implements rfc7807
func formatErrorMessage(status string, v interface{}) string {
	str := ""
	metaValue := reflect.ValueOf(v).Elem()

	if metaValue.Kind() == reflect.Struct {
		field := metaValue.FieldByName("Title")
		if field != (reflect.Value{}) {
			str = fmt.Sprintf("%s", field.Interface())
		}

		field = metaValue.FieldByName("Detail")
		if field != (reflect.Value{}) {
			str = fmt.Sprintf("%s (%s)", str, field.Interface())
		}
	}

	return strings.TrimSpace(fmt.Sprintf("%s %s", status, str))
}